Hydraulic fracturing increases the flow of desirable fluids such as oil and gas from a subterranean formation and involves placing a fracturing fluid into a subterranean formation or zone at a rate and pressure sufficient to impart a stress in the formation or zone with attendant production of a fracture in the formation or zone. Some fracturing fluids contain a viscosifying or gelling agent such as a polysaccharide that breaks shortly before or after placement in the formation.
Beyond creating the fracture, the fracturing fluid also transports a proppant into the fracture. The proppant is supposed to keep the fracture open after release of the hydraulic pressure. Further, the proppant establishes conductive channels in which the desirable fluids flow to the borehole. Since the proppant provides a higher conductivity than the surrounding rock, the fracture has greater potential for production of hydrocarbons. However, some fracturing fluids break before the fracture closes, and the proppant separates from the fracturing fluid and settles at the bottom of the fracture. In this situation, the proppants settle and concentrate at the bottom of the fracture, and thus the geometry of the fracture and well productivity is impaired.
Accordingly, compositions and methods that provide relatively high permeability and that enhance the production of hydrocarbons from fractured formations are highly desired.